Why researchers are developing robots that look and act like bats

Search and rescue operations often take place in areas where human movement is difficult due to extreme weather, rough terrain, and hazardous conditions such as smoke and dust.

Researchers at Worcester Polytechnic Institute (WPI) hope to send bat-inspired robots on these missions instead of humans.

WPI professor Nitin J. Sanket and his team have developed a small flying robot that fits in the palm of your hand and uses ultrasound waves like a bat. These robots use AI-powered software to remove noise from the ultrasound signals collected by the devices, allowing them to spot obstacles within a two-meter radius.

“Search and rescue is done on foot,” Sanket told TechCrunch. “There are a lot of people walking around with flashlights in very harsh conditions and risking their lives to save others. We thought drones were the answer because they can cover a large area very quickly. Drones are agile and can act quickly.”

Sankett has long been fascinated by aerial robots and drones and how the technology can be adapted to real-world situations. During his PhD, his advisor challenged him to create the smallest robot possible, which sparked his research into building smaller machines inspired by biology.

“At that point we had to rethink what a drone was. It was about going back to biology, because biology can do this better than we can today,” Sankett said. “How do insects and birds do that with very limited computing power and such great sensing equipment? Their eyes aren’t that great, their brains are very small, but they’re still able to perform these amazing feats of flight. So we started looking into that, and that’s what gave rise to my PhD thesis.”

Sankett has built a prototype of a robotic beehive made up of small drones that can pollinate flowers. Despite his efforts, he realized that this application was probably a moonshot and started thinking about areas where biologically based robots could bring about change faster, which led to his current project.

The main challenge for search-and-rescue robots has been building one with the necessary sensors and flight technology without making it too large, expensive, or energy-intensive.

Sankett said he turned to ultrasonic sensors, which are used in automatic faucets, because they require very little electricity. This approach worked, but the robot’s built-in propellers produced too much noise, overloading the sensors’ ability to detect obstacles.

To solve this problem, they returned to bats.

“Bats have these specialized tissues in their noses, ears, and mouths that adaptively change thickness and density to adjust how they hear and sing,” Sankett said. “We were like, ‘Okay, that’s super cool.’ Can we do something like that? We designed a 3D-printed structure that we put in front of the robot, and it basically does the same thing. [functionally, as] What bats do is change the shape of the sound itself. ”

Now that they have the robot working, they’re moving on to the next challenge: increasing its speed.

“We humans like to try to mimic a lot of the things the human brain does,” Sankett said. “We tend to forget how amazing other animals that are much smaller than us are. Especially insects and birds, which are much smaller, can actually do amazing navigational skills, but I don’t think we see that very often. I think we should think about it more as scientists and not just as engineers.”